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Oil change question

  • Thread starter Thread starter 1968jcode
  • Start date Start date Aug 11, 2019
1

1968jcode

New Member
Aug 8, 2019
4
0
1
New york
Aug 11, 2019
#1
  • Aug 11, 2019
  • #1
What is the best brand and viscosity to use in my 1968 302 4b motor ?
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Aug 19, 2019
#2
  • Aug 19, 2019
  • #2
Hi, This a freshly built motor, or one that’s seen some miles?
-John
 
1

1968jcode

New Member
Aug 8, 2019
4
0
1
New york
Aug 19, 2019
#3
  • Aug 19, 2019
  • #3
08GT500 said:
Hi, This a freshly built motor, or one that’s seen some miles?
-John
Click to expand...
158000 not rebuilt that I am aware of.
 

zookeeper

Founding Member
Aug 25, 2001
3,415
63
109
Rogue River, Oregon
Aug 19, 2019
#4
  • Aug 19, 2019
  • #4
I use Valvoline 20-W50 VR1 since it has zinc. My engine only has about maybe 5K miles on it, I change it once a year (maybe 800 miles) and it doesn't use oil, slow any signs of trash or cause any other problems. I live in Southern Oregon where summer temps get 100+ daily and my car sees a good mix of freeway and city, even though it's limited mileage.
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Aug 19, 2019
#5
  • Aug 19, 2019
  • #5
Hi,
Simple answer for a change: Viscosity, 10-40 in the Summer, 10-30 in the Winter (if it’s driven, then). High mileage, Conventional. Penzoil High Mileage.
Run an HDDP Additive within the Oil.
Never go above 15/50Wt.
OE Filter, K&N, Mobil 1, etc.
You’ll find everyone has they’re own Oil preference, & despite the question is simple, answer is much more complex. I’ll explain.
Guessing this is relatively stock & you’re running a Flat Tappet Hydraulic, or Solid Cam. Not a Roller Cam-correct?
Do you have a Mech. Oil pressure Gauge?, if not, I’d recommend installing one.
Motor’s needs for Oil Wt. of is a combo of Both OE recommendations & Specifics of your engine & how it runs.
If you start it up after 24Hr’s & Hydraulic lifters clack away for a few minutes upon startup, low Oil Pressure at Idle when Cold, jump up a viscosity grade. Not more viscous than necessary, the components within the Oil are of equal importance.
Viscosity and Oil Type is Based on:
1) Bearing clearance setup. Mains-Rods.OE, or rebuild spec’s.
2) Achieving >/=25PSI at Idle, then 10psi pressure per 1,000 RPM up to 5,000 RPM’s, 50 psi.
3) What Oil type has been run in it, how often was it changed. Was it already converted to a Synthetic blend after the Rings were seated?
4) Mileage.
Independent of ANY of the above..
I’ve run ZDDP & Zinc additive(s) ever since ZDDP levels began to decline, flat Tappet Cam’s require minimum levels of ZDDP.

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ZDDP has been an important additive to engine oils for >70 yrs, has an excellent track record at protecting the sliding metal-to-metal cam lifter interface by creating a film on cams and flat lifter contact points in response to extreme pressure and heat.
The film of zinc and phosphorus compounds provides a sacrificial wear surface protecting the base metal of the cam and lifter from wear. They’ve been removing it for Cat’s protection, large duration between Oil changes.
Synthetics are worth it if you have a strong, high mileage Motor, it’ll halt wear in the 90% range.
Some older, high mileage Motors May burn Oil as result of it, or old Seals May leak. It may be run providing the Viscosity and HDDP levels are present. If the Motors been taken care of across its miles, good Oil Pressure, no leaks, then it’s worth considering.
-Pennzoil is great, has adequate levels of HDDP, Detergent, Full Synthetic, Detergent type, HDDP is adequate, it’s made for High Mileage app’s. .
- Mobil 1 High Mileage Synthetic, 15-50 Wt. is required to get the HDDP levels, designed for high mileage, Detergent.
My OWN preferences:
- Amsoil or Valvoline, Quaker State, Pennzoil are what I run for Conventional Oil’s.
- Ford has their own Synthetics, I run that, Mobil 1, Royal Purple, Valvoline, Pennzoil for Synthetic Oil’s.
Run an OE Filter, Or K&N, Mobil 1. Makes no difference regarding Conventional or Partial/Full Synthetic Oil’s
Sorry for the dissertation, but there’s a lot to the subject, Type in Zinc, HDDP, view the importance in older app’s.
If you have any questions about anything I’ve listed, please- feel free to ask!
- John
 
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